Separable connectors for electric conduits and cables



Feb. 26, 1963 F. PAASCHE 3,079,580

SEPARABLE CONNECTORS FOR ELECTRIC CONDUITS AND CABLES Original Filed March 11, 1958 3 Sheets-Sheet 1 Feb. 26, 1963 F. PAASCHE 3,079,530

SEPARABLE CONNECTORS FOR ELECTRIC CONDUITS AND CABLES Original Filed March 11, 1958 3 Sheets-Sheet 2 r I l 17a drama Unite The present invention relates to separable connectors for multi-wire insulated electric lines and cables.

The present application is a continuation application of my copending application Serial No. 720,738 filed March 11, 1958 noW abandoned.

In such connectors, the dstance between individual conductors as well as that between the conductors and the grounded envelope depends primarily upon the necessary creep distance and upon the air gap required to prevent breakdown by surface conduction and spark-over. In the cable connectors of known construction, a small gap remains between the insulating layers surrounding the joined conductor ends which necessitates a substantial increase of the diameter at that point of connection as compared with the diameter of the cables themselves.

An important object of the invention is to provide a connector between two multi-wire cables or electric lines whose diameter is only slightly increased over the diameters of connected parts.

Another object of the invention is to provide an air-, moisture and dustproof connector of the above character.

An additional object of the invention is to provide a relatively simple and readily separable connection between two multi-wire cables or electric lines consisting of a number of separate insulated conductors.

A further object of the invention is to provide a novel connector for multi-wire cables and electric lines in which the contact resistance is reduced to a minimum.

A still further object of the instant invention is to provide a connector of the above character which is so con structed as to prevent formation of air pockets and attendant ionization phenomena.

A yet further object of my invention is provide a connector for multi-wire electrical leads which is constructed with a view to prevent formation of creep currents.

A concomitant object of the invention is to provide a connector of the above character which may be prefabricated and partially assembled at the place of manufacture, thus requiring very little time for final assembly at the place of actual use.

An additional object of the invention is to provide a connector for multi-wire cables and the like whose outer diameter is so small that the so connected cables may be wound onto and stored on cable drums in customary manner.

The above and many other objects of the invention are attained by the provision of a novel connector in which the bare ends of joined conductors as well as the contact elements therebetween are surrounded by continuous, tightly joined, dense layers of insulating material to effectively prevent any direct communication of air between the individual conductors themselves or between the conductors and the ground. To that end, each terminal is surrounded by an insulating material whose adjacent end surfaces are so shaped as to define therebetween suitable recesses for reception of elastic sealing elements which latter surround each individual conductor and, after a rigid connection between the two halves of my detachable union is established, for example, by means of threaded bolts or the like, are at least partly compressed to effectively seal the conductors from each ing layers.

Efiihfibb ;Pa.tented Feb. 26, 1953 other and from the surrounding grounded envelope in air-, moistureand dustproof manner and to thus efiectively prevent the occurrence of creep distances. The insulating layer is preferably made of a casting resin or the like and, in accordance with my invention, surrounds each elastic sealing element in such a way as to contribute by its own configuration to the air-, moistureand dustproof seal around each conductor.

In accordance with a modification of my invention which is particularly suitable for application in connection with high-tension conduits and cables, each condoctor is surrounded by a separate layer of insulating material, and the meeting surfaces of insulating layers at the points of connection are again formed with suitable projections and recesses to form therebetween a first seal which is completed by the above-referred-to elastic sealing members surrounding each contact point of the joined conductors between the meeting end surfaces of insulat- Each insulating layer is surrounded by a shell of current conducting metallic material, these shells being so formed as to telescopically engage with one another when the connection is completed and to thus form the outer barrier between each conductor and the surrounding air. The insulating material completely fills the interior of each shell to expel the air therefrom and to thus prevent ionization phenomane by preventing formation of direct air paths for the electric lines of force between the conductors and surrounding grounded metallic envelope.

The formation of creep currents and the ionization in the area of my novel connector are prevented by the provision of the above mentioned castin -resin insulating layer which surrounds the tubular insulator adjacent to the bare end of each conductor as Well as the bare ends of conductors and the customary contact elements by forming a single insulating bed therearound, or a separate insulating layer may be applied in surrounding relationship to each individual conductor of a high-tension multi-wire cable. In the latter case, and as above mentioned, the individual conductors at the point of connection are surrounded by their own envelopes consisting of two tubular metallic members joined end-to-end which receive and tightly seal the insulating layers and the elastic sealing members therebetween.

Since the novel connector is of only slightly increased outer diameter, the so joined cables or conduits may be wound and stored on drums without requiring special receptacles or the like. Accordingly, the connectors may be applied to cable ends at the place of manufacture and the connector halves thereupon require very little time for final assembly at the point of actual use. This is of considerable advantage, since the installation of certain parts on the ends of a cable occurs with greater facility in a plant than at the locale of use where the halves of cable union are merely coupled to each other by drawing tight the grounded shells against each other. For example, in mines and other locales where the final connection between cable ends must often be completed under quite difiicult working conditions, the novel union is of considerable advantage not only for use with continuously displaced cables but also in cases when cables with e.g. a synthetic coating are used for extended periods of time and thereupon transferred to another location of use.

Moreover, the novel connector may be used with considerable advantage for detachably connecting conduits or cables with electric appliances by mounting one half of the connector on such apparatus. The connection of high-tension lines to certain apparatus, such as transformers and electric motors, is greatly simplified and the safety operation is increased especially in dusty and moist areas.

Other features, advantages and attributes of the novel connector will become apparent and will be pointed out in greater detail in the course of the following description of two embodiments selected for illustration in the accompanying drawings, wherein:

FIG. 1 is a transverse section through a connector between two four-wire cables, the section being taken on line AA in FIG. 2;

FIG. 2 is a longitudinal section through the cable connector taken on line -3 of FIG. 1;

FIG. 3 is a transverse section through a modified connector between two three-wire cables, the section being taken on line C-C of FIG. 4;

FIG. 4 is a longitudinal section through the modified cable'conriector taken on line DD of FIG. 3;

FIG. 5 is a partial longitudinal section showing some *detail of the embodiment of FIG. 2 in-an enlarged scale;

and

FIG. 6 is a partial longitudinal section of the embodiment of FIG. 4 also drawn to an enlarged scale.

Referring-first to the embodiment of FIGS. 1, 2 and '5,

:there-is shown a four-wire low tension line whose cable 1a and 1b are conductively connected to each other within a metallic envelope consisting of a first substantially cylindrical member 7a surrounding and projecting beyond the end portion of cable 1a, and a similar member 7b which is fixed in surrounding relationship to and extends beyond the end of cable 1b. Leads 3a and 3b extend beyond the ends of their sheaths 2a, 2b With'the conductors 21a, 21b

projecting from the ends of respective insulating layers 4a, 4b to be firmly received in female and male contact tormed with complementary, preferably concentric rings and recesses, indicated at 9, whichareso'disposed that the projecting rings at the end face'of hardened insulating member 6a fit into the recesses in the member 6b and vice -versa. In order to positively prevent penetration of air,

dust or moisture into the cable connector and into contact with elements a,'5b, the end faces of insulating members 6a, 6b together with exposed outer face portions 5c and 5d of elements 5a and 5b, respectively, define additional recesses 8a which, when the envelope halves 7a, 7b are placed end-to-end as shown in FIG. 2, define annular spaces for reception of elastic rings 8, preferably of circular cross-sectional contour, which latter tightly close the sole path for entry of aeriform, liquid or solid media to said contact elements and to conductors 21a, 21b. In addition and in order to prevent cold flow of the elastic material of which rings 8 are made into thespace between the adjacent end faces" of members 6a, 6b as well as into the slots between the prongs of male contact elements 5b and thence into the female members 5d, the end face of each resinous insulator 6a, 6b may define additional annular recesses for'reception of rings '11 made of a pressure-resistant material, for example, polyamide, which latter thus positively prevent cold flow of elastic material of rings 8 either outwardly toward member 7b or inwardly toward said female and male contact elements. Rings 11 may be-fixed to insulating member 6a or 6b before the two cable 'ends are connected to'each other.

The end faces of envelopes-7a, 7b may be-drawn tight against each other and the elastic rings 8 thus-compressed by a number of threaded bolts received in suitable brackets fixed to the adjacent peripheral portions of memhers 7a, 7b which latter may be made of aluminum'or other's'uitable current conducting metallic material.

FIGS. 3 and 4 area transverse and a longitudinal section, respectively, through the connector between cables upon received in a composite cylindrical body 13a, 13b

of aluminum or similar current conducting material. The cylinders 13a, 13b of each pair of leads 3a, 3b are led through the apertures in centering discs 14a, 14b which latter are held in spaced relationship by a number of bolts and nuts indicated at 15f, whereby the enlarged end portions of cylinders 13a telescopically receive the adjacent end portions of cylinders 13b to tightly enclose and slightly compress the elastic sealing rings 8. As before described in connection with FIGS. '1 and 2, outer envelopes 7a, 7b' tare connected to each other by a number of threaded bolts 10' passing through suitable brackets attached to member 7b and extending into tapped bores provided in aligned brackets attached to member 7a. As shown in FIG. 4, member 7af-has welded or otherwise se cured'thereto a cylindrical collar which telescopically receives the adjacent end portion of member 7b'- and also Zcarriesthe brackets into which the threaded ends of bolts 10' extend. In this embodiment, members 7a, 7b' merely form an outer envelope which may be taken apart with- 1 grounded envelopes 17a, 17b of each lead 3a, 3b. The

free end of each cylinder-13a, 13b is sealed by aresilient ring 18a, 18b, respectively, whose purpose is to permit continuation of work to complete the connection before the material of resinous fillers 6a, 6b hardens. At the same time, rings 18a, 18b augment the dielectric strength of the resin encased connections.

It is advisable to'fasten cylindrical elements'13a', 13b in respective centering discs 14a, 14b before the terminals of conductors 21a, 2112 are electrically connected to each other by coupling of contact'elements 5a, 5b. As snown, cylinders 13a, 13b may be formed with peripheral collars with diametersg'reater than the diameters of apertures in discs 14a, 14b to facilitate proper positioning of said cylinders before the bolts and nuts 15 are drawn tight. However, such connection of cylinders 13a 13b with discs 14a and 14b would render the -having conical outwardly flaring surfaces to be received m seats of respective female and male contact elements 5a, 5b. The adjacent ends of contact elements 5a, 5b are formed w th conical recesses forming seats for the outwardly flaring conical ends of extension pieces 19a,

19b, and the rigid connection between these elements is completed by members 20a, 20b which extend into bores provided in members 19a, 1%, respectively. The heads of members 20a, 20b are adjacent to the "easily accessible front end faces of contact elementsSa', 5b, respectively. By conically forming the rear end portions of members 19a, 19b and bypr-oviding complementary recesses in the adjacent'end'faces of contact "elements "512', 5b',- the contact resistance to -'a-' minimum at these points is reduced The novel separable connector may be applied with slight modifications to many types of cables regardless of the construction, insulation and other characteristics of the latter. For example, the contact elements need not necessarily be male and female fashion as long as they allow for sufficient longitudinal displacement neces sary to compress the elastic rings 8 and 8. Similarly, the rings 8, 8' as well as tubes 12a, 12b and'the current-conducting parts of the novel connector may be chosen from a Wide variety of materials with requisite characteristics. All such and many other modifications are believed to be within the nature and spirit of my invention whose true scope is defined by the appended claims.

What I claim and desire to protect by Letters Patent is:

1. A connector for forming a separable electrical connection between the terminals of two multi-wire electric lines, comprising, in combination, a pair of complementary parts of solid, dense insulating material adapted to be releasably joined in end-to-end relationship, each of said parts surrounding at least one terminal of one of said lines; annular resilient means of insulating material disposed between the adjacent ends of said parts; annular means of pressure resistant insulating material disposed within and outwardly adjacent to each of said resilient means between the adjacent ends of said parts; and means for releasably connecting said parts in endto-end relationship in such a way as to compress said resilient means therebetween and to establish electrical connections between the terminals of one of said lines and the terminals of the other of said lines, whereby said means of pressure-resistant material prevent cold flow of the material of said resilient means between the ends of said parts.

2. A device for forming a separable electrical connection between the terminals of two multi-wire electric lines or cables, comprising, in combination, -a contact element connected to each terminal of each of said lines; a pair of complementary parts of solid, dense insulating material adapted to be releasably joined in end-to-end relationship, each of said parts surrounding at least one terminal and its contact element of each of said lines; resilient means of insulating m terial disposed between the adjacent ends of said parts; pressure resistant means inwardly and outwardly adjacent to each of said resilient means between the adjacent ends of said parts; and means defining a metallic envelope about each of said parts and comprising means for separably maintaining said parts in end-to-end relationship in such a Way as to compress said resilient means therebetween sufiiciently to form an airtight insulating layer about each of said terminals and to electrically connect the contact elements of one of said lines with the contact elements of the other of said lines.

3. A connector for a pair of cables each including a plurality of conductors and each conductor having an insulated portion and a bare end, said connector comprising, in combination, a contact element connected to the bare end of each of said conductors; a pair of tubular shells of metallic material each having an end dispose in surrounding relationship with respect to one of said cables and receiving therewithin the insulated portions and the contact elements of the respective one of said cables, each of said shells having another end adapted to be brought into end-to-end relationship with each other; a filler ofisolid, dense insulating material in each or" said shells surrounding the insulating portions and contact elements therewithin, each of said fillers having an end surface adjacent to said last mentioned end of one of said shells with said end surface defining an annular recess about each of said contact elements surrounded thereby; means for releasably connecting said shells in such a way that said end surfaces of said fillers at least partially abut against each other whereby the contact elements of one of said cables are in surface-to-surface contact with the contact elements of the other of said cables; resilient means of insulating material disposed in said recesses between the end surfaces of said fillers for airtightly sealing said connector; and means of pressure resistant insulating material disposed between the end surfaces of said fillers for preventing cold flow of the material of said resilient elements outwardly toward said shells and inwardly toward said contact elements.

4. A connector for a pair of multi-conductor electric lines, each conductor having an insulated portion and a bare end, said connector comprising, in combination, a male contact element conductively connected to the bare end of each conductor of one of said lines; a female contact element conductively connected to the bare end of each conductor of the other of said lines and receiving one of said male contact elements; a tubular member of insulating material surrounding the insulated portion and the contact element of each of said conductors; a tubular metallic shell surrounding each of said tubular members; a resilient ring for sealing the end of each of said shells distant from the contact element therewithin; a filler of casting resin within each of said tubular members for surrounding the insulating portion and contact element therewithin, each of said fillers having an end surface adjacent to the contact element surrounded thereby and defining an annular recess about the contact element; means for releasably connecting the shells of one of said cables with the shells of the other of said cables in such a way that said end surfaces of said fillers therewithin at least partially abut each other; resilient means of insulating material disposed in the recesses between the end surfaces of said fillers and adapted to be compressed by said last-mentioned means; means for maintaining the shells of each of said cables in spaced relationship; and means defining a metallic envelope about said shells, said last mentioned means comprising a first cylindrical member having one end surrounding a portion of one of said cable 2, second cylindrical member having one end sursounding a portion of the other of said cables; and means for releasably connecting the free ends of said cylindrical members.

5. A connector for a pair of multi-conductor electric lines, each conductor having an insulated portion and a bare end, said connector comprising, in combination, extension means conductively connected to the bare end of each of said conductors; each of said extension means having an outwardly tapering recess; a contact element for each of said extension means and havin a substantially conical portion extending into the recess in one of said extension means; means for releasably connecting each of said contact elements to one of said extension means; a tubular member of insulating material surrounding the insulated portion as well as the extension means and the contact element of each of said conductors; a tubular shell of metallic material surrounding each of said tubular members; a resilient ring for sealing the end of each of said shells distant from the con act element therewithin; a filler of casting resin within each of said tubular mem bers for surrounding the insulating portion and the extension means and the contact element therewithin, each of said fillers having an end surface adjacent to the con tact element surrounded thereby and defining an annular recess about the contact element; means for releasably connecting the shells of one of said cables with the shells of the other of said cables in such a Way that said end surfaces of said fillers therewithin at least partially abut each other and that the contact elements therewithin are in surface-to-surface contact with each other; resilient means of insulating material disposed in the recesses between the end surfaces of said fillers and adapted to be compressed by said last mentioned means; means of pressure resistant material disposed between the end surfaces of said fillers for preventing cold flow of the material of said resilient means outwardly toward said shells and inwardly toward said contact elements; means for maintaining the shells of each of said cables in spaced relaxtionship; and means defining a separable metallic envelope about said shells.

6. A device for forming a separable electrical connection between the terminals of two multi-wire electric lines comprising, in combination, a contact element fixedly connected to each terminal of each of said lines, associated pairs of contact elements being in detachable conductive connection, one contact element of each associated pair of contact elements being a male contact element and the other a female contact element receiving the 1 corresponding male contact element; a pair of comple- 1 extending about each of said associated pairs of contact elements and respectively protruding from and into said end faces and said rims extending into said'recesses, when said male contact elements are partly received in said female contact elements, to form with said end faces and said exposed outer surface portions outwardly closed annular spaces of predetermined volume about each associated pair of contact elements; annular resilient means of insulating material disposed in each of said annular spaces and surrounding each of said associated pairs of contact elements; and means operatively connected to said insulating means for releasably connecting said contact elements to each other and to positively moving said end faces of said insulating means towards each other to simultaneously reduce said predetermined volume of said outwardly closed spaces to compress thereby said resilient means and to force the same against said end --'faces of said insulating means and said exposed outer surface portions of said contact elements in such a way that when said contact elements are completely connected to each other any air-space adjacent said exposed outer surface portions and said adjacent end faces of said insulating meansis completely filled by said compressed resilient means and so that creep currents between adjacent pairs 7 of contact elements are prevented.

7. A device for forming a separable electrical connection between the terminals of two mnlti-wire electric lines, comprising, in combination, a contact element fixedly connected to each terminal of each of said lines,

associated pairs of said contact elements being in detachable conductive connection, one contact element of each associatedpair of contact elements being'a male contact element received in a correspondingfemale contact element; :1 pair of complementary parts of solid, hard insulating material adapted to be reieasabiy joined in endto-end relationship, said parts, respectively, surrounding said terminals and the contact elements of said lines, sm'd contact elements having at adjacent end faces of said insulating parts exposed outer surface portions, said insulating parts being respectively formed with complementary annular rims and recesses extending about said associated pairs of contact elements and respectively protruding from and extending into said adjacent end faces and defining together with said end faces and said exposed outer surface portions, when said male contact elernents are partly received in said female contact elements, outwardly closed annular spaces about each associated pair of contact elements and said closed annular spaces being reduced in volume during full engagement of said contact elements; annular resilient means of insulating material disposed in each of said annular spaces and surrounding each associated pair of contact elements;

, and means for releasably connecting the-associated pairs of contact elements together by positively moving said end faces of said insulating parts toward each other to reduce the volume of said outwardly closed spaces so as to compress said resilient means in said annular spaces sufficiently to form'an airtight insulating layer about each a of said associated pair of contact elements and in such a way that when said contact elements are completely connected any air space adjacent said exposed outer surface portions of said contact elements is completely filled by said compressed resilient means and so that any air gap between said contact elements andsaid insulating parts at said adjacent faces of the latteris sealed by said compressed resilient means.

each terminal of each'of said lines, each of said members having an end face and surrounding the respective one of said terminals and the contact elements connected thereto, members of associated pairs of members of said lines being adapted to be joined in end-to-end relationship, said contact elements having atsaid adjacent end faces exposed outer surface portions; a tubular shell of conductive material surrounding eachvoi said members, oneof the tubular shells surrounding one of the members in each associated pair of members projecting beyond the end face thereof and slidingly engaging a peripheral surface portion of the shell surrounding the other member of the respective pair of associated members to form together with the corresponding end faces and said exposed outer surface portions, when said male contact elements are partly received in said female elements, outwardly closed annular spaces about each associated pair of contact elements and said closed annular spaces being reduced in volume during full engagement of said contact elements; annular resilient means of insulating material disposed in each of said annular spaces and surrounding said end faces of said insulating members toward each other to reduce the volume of said outwardly closed spaces-so as to compress said resilient means in said annular spaces sufiiciently to form an airtight insulating layer about each of said associated pair of contact elements and in such a way that when said contact elements are completely connected any air space adjacent said exposed outer surface portions of said contact elements is completely filled by said compressed resilient means and so that any air gap between said contact elements and said insulating members at "said adjacent faces of the latter is sealed by said compressed resilient means.

No references cited. 

1. A CONNECTOR FOR FORMING A SEPARABLE ELECTRICAL CONNECTION BETWEEN THE TERMINALS OF TWO MULTI-WIRE ELECTRIC LINES, COMPRISING, IN COMBINATION, A PAIR OF COMPLEMENTARY PARTS OF SOLID, DENSE INSULATING MATERIAL ADAPTED TO BE RELEASABLY JOINED IN END-TO-END RELATIONSHIP, EACH OF SAID PARTS SURROUNDING AT LEAST ONE TERMINAL OF ONE OF SAID LINES; ANNULAR RESILIENT MEANS OF INSULATING MATERIAL DISPOSED BETWEEN THE ADJACENT ENDS OF SAID PARTS; ANNULAR MEANS OF PRESSURE RESISTANT INSULATING MATERIAL DISPOSED WITHIN AND OUTWARDLY ADJACENT TO EACH OF SAID RESILIENT MEANS BETWEEN THE ADJACENT ENDS OF SAID PARTS; AND MEANS FOR RELEASABLY CONNECTING SAID PARTS IN ENDTO-END RELATIONSHIP IN SUCH A WAY AS TO COMPRESS SAID RESILIENT MEANS THEREBETWEEN AND TO ESTABLISH ELECTRICAL CONNECTIONS BETWEEN THE TERMINALS OF ONE OF SAID LINES AND THE TERMINALS OF THE OTHER OF SAID LINES, WHEREBY SAID MEANS OF PRESSURE-RESISTANT MATERIAL PREVENT COLD FLOW OF THE MATERIAL OF SAID RESILIENT MEANS BETWEEN THE ENDS OF SAID PARTS. 